I cannot copy a directory named "2021"

Hi there,
Weird issue, using the 1.5.15 version on Ubuntu 18.04.
I have it with multiples vaults: when I try to copy a directory named “2021” on the vaults, I have the following error message:
the file exists
But it doen’t not exists, even I refresh Nautilus, or if I do a ls command in the parent directory.
I doesn’t have the error for others directories, it’s only if the name is “2021”, which is very strange.
You can see it in this attachment:

I can create manually the 2021 directory, but when I use Cryptomator, I copy parents directories, si it’s not a solution to create them manually (I have these “2021” directories in many vaults).
I hope you can help me to pass through this issue.
Thank you